This invention relates to radial engines.
This invention has particular but not exclusive application to internal combustion engines, and for illustrative purposes particular reference will be made to such application. However, it is to be understood that this invention could be used in other applications, such as fluid compressors or pumps which are embraced hereinafter by the term "engine".
Currently, most engine designs use circular-section single acting pistons supported by a crankshaft for reciprocation within cylinders to and from a cylinder head against which the combustion pressures react or the fluid is compressed. Such designs have been favored primarily because of the simplicity of sealing against gas pressure between circular pistons and circular cylinders bores. The concentration of engineering development of piston engines has maintained this design in the premier position among internal combustion engines and compressors for many years.
However, such engines have a number of disadvantages, including large size and weight relative to output power and, in many instances, inherent vibration. They also suffer from friction losses due to the reciprocal motion of the pistons which results in wear and power consumption on the side thrust faces of the pistons and cylinders. They are also relatively complex due to the need, in their most common four-stroke form, to provide inlet and outlet poppet valves and associated operating mechanisms for each cylinder. Known radial engines have the disadvantage that they are even more complex due to the requirement to provide individual drives to each of the spaced cylinder heads for the respective inlet and outlet valves.